"Bristle millipede" redirects here. Not to be confused with the bristly millipede, Polyxenus lagurus.
Polyxenida is an order of millipedes readily distinguished by a unique body plan consisting of a soft, non-calcified body ornamented with tufts of bristles – traits that have inspired the common names "bristly millipedes" or "pincushion millipedes". There are at least 86 species in four families worldwide, and are the only living members of the subclass Penicillata.
Polyxenida differ from other millipedes in having a soft, non-calcified exoskeleton, unique tufts of bristles or setae, fewer legs (no more than 17 pairs), and an absence of copulatory appendages in males. Individuals are small, not exceeding 7 millimeters (0.28 inches). Adults in most species have 13 pairs of legs, but in one species (Lophoturus madecassus), they have only 11 pairs of legs, and in one genus (Phryssonotus), they have 17 pairs of legs, except for one species (Phryssonotus brevicapensis) in which they (along with those in one other species, Condexenus biramipalpus) have 15 pairs of legs.[1] Millipedes in this order develop by hemianamorphosis.[2]
Defenseedit
Bristly millipedes lack the chemical defenses and hard exoskeleton of other millipedes,[3] and instead employ a unique defense mechanism: the distinctive barbed bristles can easily detach and become entangled in the limbs and mouth-parts of predatory insects, effectively immobilizing them.[4]
Reproductionedit
Male Polyxenidans lack the modified sperm-transferring appendages (gonopods) found in most other millipede groups. As a result, sperm transfer is indirect: males deposit a spermatophore that is subsequently picked up by females.[5]
Many species reproduce asexually by way of parthenogenesis, wherein females lay eggs without mating and males are absent or rare.[6]
Classificationedit
Phryssonotus brevicapensis (Synxenidae), a species from South Africa described in 2011[7]
Polyxenida is the only living order of the subclass Penicillata, the basal subclass of millipedes. Penicillata is the sister group of all other living millipedes: the infraclasses Pentazonia and Helminthomorpha.[8][9]
In 2003 the Polyxenida contained 159 valid species and/or subspecies,[10] although at least eight new species have been described since 2010.[7][11][12]
^Enghoff, Henrik; Golovatch, Sergei; Short, Megan; Stoev, Pavel; Wesener, Thomas (2015-01-01). "Diplopoda — taxonomic overview". Treatise on Zoology - Anatomy, Taxonomy, Biology. The Myriapoda, Volume 2: 363–453. doi:10.1163/9789004188273_017.
^Enghoff, Henrik; Dohle, Wolfgang; Blower, J. Gordon (1993). "Anamorphosis in Millipedes (Diplopoda) — The Present State of Knowledge with Some Developmental and Phylogenetic Considerations". Zoological Journal of the Linnean Society. 109 (2): 103–234. doi:10.1111/j.1096-3642.1993.tb00305.x.
^Shelley, Rowland M. "The Myriapoda (Millipedes, Centipedes) Featuring the North American Fauna". Retrieved 12 October 2013.
^Eisner, T; Eisner, M; Deyrup, M (1996). "Millipede defense: use of detachable bristles to entangle ants". Proceedings of the National Academy of Sciences of the United States of America. 93 (20): 10848–51. Bibcode:1996PNAS...9310848E. doi:10.1073/pnas.93.20.10848. PMC38244. PMID 8855269.
^Shelley, Rowland M. (1999). . The Kansas School Naturalist. 45 (3): 1–16. Archived from the original on 2016-11-12. Retrieved 2013-10-12.
^Barnes, Robert D. (1987). "15. The myriapods". Invertebrate zoology (5th ed.). Philadelphia: Saunders College Pub. pp. 674–683.
^ abNguyen Duy - Jacquemin, Monique; Uys, Charmaine; Geoffroy, Jean-Jacques (2011). "Two remarkable new species of Penicillata (Diplopoda, Polyxenida) from Table Mountain National Park (Cape Town, South Africa)". ZooKeys (156): 85–103. doi:10.3897/zookeys.156.2211. PMC3253573. PMID 22303097.
^Sierwald, Petra; Bond, Jason E. (2007). "Current Status of the Myriapod Class Diplopoda (Millipedes): Taxonomic Diversity and Phylogeny". Annual Review of Entomology. 52 (1): 401–420. doi:10.1146/annurev.ento.52.111805.090210. PMID 17163800.
^Shear, W (2011). "Class Diplopoda de Blainville in Gervais, 1844. In: Zhang, Z.-Q.(ed.) Animal biodiversity : an outline of higher-level classification and survey of taxonomic richness" (PDF). Zootaxa. 3148: 159–164. doi:10.11646/zootaxa.3148.1.32.
^Nguyen Duy-Jacquemin, M.; J.-J. Geoffroy (2003). "A revised comprehensive checklist, relational database, and taxonomic system of reference for the bristly millipedes of the world (Diplopoda, Polyxenida)". African Invertebrates. 44 (1): 89–101.
^Short, Megan; Huynh, Cuong (2011). "The genus Unixenus Jones, 1944 (Diplopoda, Penicillata, Polyxenida) in Australia". ZooKeys (156): 105–122. doi:10.3897/zookeys.156.2168. PMC3253574. PMID 22303098.
^Short, Megan; Huynh, Cuong (2013). "Four new species of Unixenus Jones, 1944 (Diplopoda, Penicillata, Polyxenida) from Australia". ZooKeys (278): 75–90. doi:10.3897/zookeys.278.4765. PMC3677348. PMID 23794829.
^Duy-Jacquemin, MN; Azar, D (2004). "The oldest records of Polyxenida (Myriapoda, Diplopoda): New discoveries from the Cretaceous ambers of Lebanon and France". Geodiversitas. 26 (4): 631–641.
^Shear, William A.; Edgecombe, Gregory D. (2010). "The geological record and phylogeny of the Myriapoda". Arthropod Structure & Development. 39 (2–3): 174–190. doi:10.1016/j.asd.2009.11.002. PMID 19944188.
^Kraus, O; C. Brauckman (2003). "Fossil giants and surviving dwarfs. Arthropleurida and Pselaphognatha (Ateolocerata, Diplopoda): characters, phylogenetic relationships and construction". Verh. Naturwiss. Ver. Hamburg. 40 (5): 5–50.
polyxenida, confused, with, bristle, millipede, redirects, here, confused, with, bristly, millipede, polyxenus, lagurus, order, millipedes, readily, distinguished, unique, body, plan, consisting, soft, calcified, body, ornamented, with, tufts, bristles, traits. Not to be confused with Polyxenidas Bristle millipede redirects here Not to be confused with the bristly millipede Polyxenus lagurus Polyxenida is an order of millipedes readily distinguished by a unique body plan consisting of a soft non calcified body ornamented with tufts of bristles traits that have inspired the common names bristly millipedes or pincushion millipedes There are at least 86 species in four families worldwide and are the only living members of the subclass Penicillata PolyxenidaTemporal range Barremian Present PreꞒ Ꞓ O S D C P T J K Pg NPolyxenus lagurusScientific classificationDomain EukaryotaKingdom AnimaliaPhylum ArthropodaSubphylum MyriapodaClass DiplopodaSubclass PenicillataLatrielle 1831Order PolyxenidaVerhoeff 1934FamiliesHypogexenidae Lophoproctidae Polyxenidae SynxenidaeSynonymsSubclass Pselaphognatha Latzel 1884 Schizocephala Verhoeff 1926Order Ancyrotricha Cook 1895Segmentation of Polyxenida millipedes From top to bottom Lophoturus madecassusOther Lophoproctidae and PolyxenidaeCondexenus biramipalpus and Phryssonotus brevicapensisOther Phryssonotus Contents 1 Description 2 Defense 3 Reproduction 4 Classification 5 Fossil history 6 References 7 External linksDescription editPolyxenida differ from other millipedes in having a soft non calcified exoskeleton unique tufts of bristles or setae fewer legs no more than 17 pairs and an absence of copulatory appendages in males Individuals are small not exceeding 7 millimeters 0 28 inches Adults in most species have 13 pairs of legs but in one species Lophoturus madecassus they have only 11 pairs of legs and in one genus Phryssonotus they have 17 pairs of legs except for one species Phryssonotus brevicapensis in which they along with those in one other species Condexenus biramipalpus have 15 pairs of legs 1 Millipedes in this order develop by hemianamorphosis 2 Defense editBristly millipedes lack the chemical defenses and hard exoskeleton of other millipedes 3 and instead employ a unique defense mechanism the distinctive barbed bristles can easily detach and become entangled in the limbs and mouth parts of predatory insects effectively immobilizing them 4 Reproduction editMale Polyxenidans lack the modified sperm transferring appendages gonopods found in most other millipede groups As a result sperm transfer is indirect males deposit a spermatophore that is subsequently picked up by females 5 Many species reproduce asexually by way of parthenogenesis wherein females lay eggs without mating and males are absent or rare 6 Classification edit nbsp Phryssonotus brevicapensis Synxenidae a species from South Africa described in 2011 7 Polyxenida is the only living order of the subclass Penicillata the basal subclass of millipedes Penicillata is the sister group of all other living millipedes the infraclasses Pentazonia and Helminthomorpha 8 9 In 2003 the Polyxenida contained 159 valid species and or subspecies 10 although at least eight new species have been described since 2010 7 11 12 Superfamily Polyxenoidea Lucas 1840 Hypogexenidae Schubart 1947 Lophoproctidae Silvestri 1897 Polyxenidae Lucas 1840 Superfamily Synxenoidea Silvestri 1923 Synxenidae Silvestri 1923Fossil history editThe earliest representatives of Polyxenida are found in Lebanese amber from the Early Cretaceous period 13 Some authors place the extinct orders Arthropleurida and Eoarthropleurida each represented by a single genus within the Penicillata as a sister group to Polyxenida 14 15 References edit Enghoff Henrik Golovatch Sergei Short Megan Stoev Pavel Wesener Thomas 2015 01 01 Diplopoda taxonomic overview Treatise on Zoology Anatomy Taxonomy Biology The Myriapoda Volume 2 363 453 doi 10 1163 9789004188273 017 Enghoff Henrik Dohle Wolfgang Blower J Gordon 1993 Anamorphosis in Millipedes Diplopoda The Present State of Knowledge with Some Developmental and Phylogenetic Considerations Zoological Journal of the Linnean Society 109 2 103 234 doi 10 1111 j 1096 3642 1993 tb00305 x Shelley Rowland M The Myriapoda Millipedes Centipedes Featuring the North American Fauna Retrieved 12 October 2013 Eisner T Eisner M Deyrup M 1996 Millipede defense use of detachable bristles to entangle ants Proceedings of the National Academy of Sciences of the United States of America 93 20 10848 51 Bibcode 1996PNAS 9310848E doi 10 1073 pnas 93 20 10848 PMC 38244 PMID 8855269 Shelley Rowland M 1999 Centipedes and Millipedes with Emphasis on North American Fauna The Kansas School Naturalist 45 3 1 16 Archived from the original on 2016 11 12 Retrieved 2013 10 12 Barnes Robert D 1987 15 The myriapods Invertebrate zoology 5th ed Philadelphia Saunders College Pub pp 674 683 a b Nguyen Duy Jacquemin Monique Uys Charmaine Geoffroy Jean Jacques 2011 Two remarkable new species of Penicillata Diplopoda Polyxenida from Table Mountain National Park Cape Town South Africa ZooKeys 156 85 103 doi 10 3897 zookeys 156 2211 PMC 3253573 PMID 22303097 Sierwald Petra Bond Jason E 2007 Current Status of the Myriapod Class Diplopoda Millipedes Taxonomic Diversity and Phylogeny Annual Review of Entomology 52 1 401 420 doi 10 1146 annurev ento 52 111805 090210 PMID 17163800 Shear W 2011 Class Diplopoda de Blainville in Gervais 1844 In Zhang Z Q ed Animal biodiversity an outline of higher level classification and survey of taxonomic richness PDF Zootaxa 3148 159 164 doi 10 11646 zootaxa 3148 1 32 Nguyen Duy Jacquemin M J J Geoffroy 2003 A revised comprehensive checklist relational database and taxonomic system of reference for the bristly millipedes of the world Diplopoda Polyxenida African Invertebrates 44 1 89 101 Short Megan Huynh Cuong 2011 The genus Unixenus Jones 1944 Diplopoda Penicillata Polyxenida in Australia ZooKeys 156 105 122 doi 10 3897 zookeys 156 2168 PMC 3253574 PMID 22303098 Short Megan Huynh Cuong 2013 Four new species of Unixenus Jones 1944 Diplopoda Penicillata Polyxenida from Australia ZooKeys 278 75 90 doi 10 3897 zookeys 278 4765 PMC 3677348 PMID 23794829 Duy Jacquemin MN Azar D 2004 The oldest records of Polyxenida Myriapoda Diplopoda New discoveries from the Cretaceous ambers of Lebanon and France Geodiversitas 26 4 631 641 Shear William A Edgecombe Gregory D 2010 The geological record and phylogeny of the Myriapoda Arthropod Structure amp Development 39 2 3 174 190 doi 10 1016 j asd 2009 11 002 PMID 19944188 Kraus O C Brauckman 2003 Fossil giants and surviving dwarfs Arthropleurida and Pselaphognatha Ateolocerata Diplopoda characters phylogenetic relationships and construction Verh Naturwiss Ver Hamburg 40 5 5 50 External links edit nbsp Arthropods portal nbsp Media related to Polyxenida at Wikimedia Commons nbsp Data related to Polyxenida at Wikispecies Polyxenida at the Encyclopedia of Life nbsp Photos of Polyxenida Retrieved from https en wikipedia org w index php title Polyxenida amp oldid 1194600440, wikipedia, wiki, book, books, library,
